An elite unit of Chinese hackers that allegedly waged a massive cyber-espionage
campaign against U.S. companies has attempted to clean up their online presence
after being identified in a public report by information security firm
Mandiant.

Since the release of the report last month, top administration officials have
called on China to take urgent steps to crack down on hacker attacks and curb
the siphoning of intellectual property from American companies.

After outing the hacker unit in its report, Mandiant executives said Tuesday
that the Chinese hackers have taken steps to clean up their tracks and have
largely stopped their activity.

"We've seen them try to clean up some of their online presence," Richard
Bejtlich, chief security officer of Mandiant, told the leaders of the Senate
Armed Service Committee's subpanel on emerging threats and capabilities at an
unclassified briefing on Tuesday. "Some of the public databases that we or
other security researchers can use to identify them, they've changed some of
those entries."

"We've seen them change some of their infrastructure so the computers they were
using to hop from China to the West, some of that has been changed but we've
been able to keep up with them," Bejtlich added.